Abstract

A type of luminescence was observed from fluorescent dye-doped polymerfilms by corona discharge excitation. The polymer film was deposited on a transparent electrode, and direct currentcorona discharge was caused in argon atmosphere using this electrode as the anode. Emission of three elemental colors, i.e., red, green, and blue, were obtained from polyvinilcarbazole filmsdoped with 4-(dicyanomethylene)-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran, 3-(2′-Benzothiazolyl)7-diethylaminocoumarin, and 1,1,4,4-tetraphenyl-1,3-butadiene, respectively. The drive current required for the luminance of 10 cd/m2 was as low as 100 μA/cm2 and the maximum quantum efficiency was 9.95 cd/A, which is nearly four orders of magnitude higher than that of the common injection type electroluminescent cells with the same material. The origin of this high efficiency can be attributed to the efficient hole blocking by the gas phase and also by concurrent effects of different luminescence processes including electroluminescence by charge recombination, photoluminescence by ultraviolet excitation, and cathodoluminescence by electron impact excitation.